* Go to organ settings>>Advanced MIDI applications>>Floating division MIDI keyboards* Select Floating division 1 keyboard* Autodetect the physical keyboard that you want to use to either control the Choir or the Great (if prompted, select "only this control")

* Go to organ settings >> keyboards* On the left, select either the choir or great division (the one that you want to be activated by default)* in the "input" dropdown menu, select "Indirect MIDI input via floating division 1, route 1"* go to the "input 2" tab * in the "input" dropdown menu, select "Indirect MIDI input via floating division 1, route 3" (the reason for selecting a second input is to enable you to cycle with a single button through the 4 routing options, as will become clear in a few moments)* On the left, select either the choir or great division (the one that you want not to be activated by default)** in the "input" dropdown menu, select "Indirect MIDI input via floating division 1, route 4"* go to the "primary input" tab * in the "input" dropdown menu, select "Indirect MIDI input via floating division 1, route 2"* Click "OK"

* go to view>>large floating control panels>>floating divisions* press the arrow buttons next to Division 1. You'll observe that you are alternately selecting the choir and the great as you cycle through the 4 routes. '* autodetect one of the Division 1 arrow buttons with the piston that you desire. Now you can use this single button to alternately select the Choir or the Great division on the physical keyboard that you assigned.